| 摘要 |
A hydraulic drive system for an access apparatus and a method of access is presented. The hydraulic drive system may include a hydraulic power unit, a hydraulic cylinder and a subsystem for limiting motion of the access system according to the position of and/or load supported by the access system. The subsystem may prevent motion, such as stowing and/or folding, when the access apparatus is supporting a load and/or is in a predetermined position. To limit motion, the subsystem may create a fluid path from the hydraulic power unit that bypasses the hydraulic cylinder, thus preventing the cylinder from moving the access apparatus. The subsystem may include a first valve that is opened when the access apparatus is in the predetermined position, and/or a second valve that is opened when the access apparatus is supporting a load. |
